In recent years, applications utilizing a wireless LAN represented by IEEE802.11 have increased. Along with this, there has been proposed a technique in which a communication apparatus readily discovers a nearby wireless LAN application and information with low power consumption. In Wi-Fi® Alliance, there is prepared a certified program called Wi-Fi Aware for discovering a usable service and information before a communication apparatus having a communication function by a wireless LAN is connected to another peripheral communication apparatus having the same function. As the basic technique of Wi-Fi Aware, Wi-Fi Alliance Neighbor Awareness Networking (NAN) specifications have been stipulated.
In NAN, a plurality of communication apparatuses having the communication function by the wireless LAN form a cluster (to be referred to as a “NAN cluster” hereinafter), and the communication apparatuses in the NAN cluster synchronize periods during which information is exchanged, thereby sharing their pieces of application information and the like. Each communication apparatus in the NAN cluster plays a master or non-master role. The communication apparatus playing the master role transmits a beacon (to be referred to as a “discovery beacon” hereinafter) for discovering a NAN cluster, thereby notifying a communication apparatus outside the NAN cluster of the existence of the NAN cluster to which the self apparatus belongs. The communication apparatus outside the NAN cluster can recognize the existence of the NAN cluster by detecting the discovery beacon, and join the recognized NAN cluster. U.S. Patent Application Publication No. 2015/0036540 describes a method for detecting a discovery beacon and joining a NAN cluster.
To discover a NAN cluster, a communication apparatus needs to detect a discovery beacon by performing a passive scan. At this time, it is useful especially for a communication apparatus, which is in a power saving state such as a power save mode, to be able to efficiently detect a discovery beacon by a short-term search. To enable the communication apparatus to efficiently detect a NAN cluster by a short-term search, it is important to use the common timing reference on both the discovery beacon transmission side (the master of the NAN cluster) and the discovery beacon detection side (the communication apparatus outside the NAN cluster).
The present invention improves the probability that communication apparatuses existing nearby can transmit and detect a predetermined signal based on the common timing reference.